A bipartisan measure backed by Colorado’s top lawmakers to seek a sales tax hike for transportation reached the end of the road Tuesday.

A state Senate panel defeated the proposal to inject $3.5 billion into improving the state’s highways along party-lines with the three Republican members citing ideological opposition to increasing taxes.

“This is a statewide solution bill,” said Senate President Kevin Grantham, R-Cañon City. “Yes, it contains things both sides may cringe at. … But we must start looking at some of these things.”

House Bill 1242 would have asked voters in November 2017 to approve a 0.5 percentage-point increase in the statewide sales tax from 2.9 percent to 3.4 percent for 20 years to help generate money for a bond measure. In addition to the 17 percent tax hike, the measure would pull $100 million from existing tax collections and reduce annual car registration fees.

The primary road projects on the list are an expansion of Interstate 25 north and south of Denver and Interstate 70 west through the mountains. But millions more would have flowed to local governments to repair crumbling local roads and expand transit options.

Now that the bill is dead, attention turns to two possible alternatives: a separate far-reaching spending bill aimed at eliminating budget cuts to hospitals that could serve as a vehicle for transportation spending and a handful of potential ballot initiatives.

“There are two weeks left,” Grantham said. “We have to look at all available vehicles in the legislative river here and see where to navigate to.”

The forecast of the legislation’s failure did not prevent four-hours of testimony from dozens who spoke in favor and against the proposal, a similar version of which won approval in the House in March.

Most supporters urged the Senate Finance Committee to allow the measure to reach the Senate floor, where it has the votes to pass, and emphasized the need to take action.

But the bulk of opponents criticized the tax hike and suggested lawmakers cut spending elsewhere to prioritize money for transportation, suggesting everything from reductions in spending on libraries to selling an airplane used by the governor.

“In some ways I feel like we should exhaust our options before we go to the taxpayers,” said Sen. Jack Tate, a Centennial Republican who acted as the swing vote to kill it.

But Sen. Lois Court, D-Denver, retorted: “Why are we afraid to ask the people of Colorado to make a decision?”

Welcome to The Spot, where The Denver Post’s politics team captures what’s happening this week — from the Colorado legislature to Denver city hall, with a stop through the halls of Congress in Washington, D.C.

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